Side-channel compressor for a fuel cell system for conveying and/or compressing a gaseous medium

Abstract

The invention relates to a side-channel compressor (1) for a fuel cell system (37) for conveying and/or compressing a gaseous medium, in particular hydrogen, comprising a housing (3); a compressor chamber (30) which is situated in the housing (3) and which has at least one encircling side channel (19, 21); a compressor impeller (2) which is situated in the housing (3) and which is arranged so as to be rotatable about a rotational axis (4), wherein the compressor impeller (2) has conveying cells (5) arranged on the impeller circumference in the region of the compressor chamber (30); and in each case one gas inlet opening (14) formed on the housing (3) and one gas outlet opening (16), which are fluidically connected together via the compressor chamber (30), in particular the at least one side channel (19, 21). The housing (3) has a respective first and second end face (32, 34) radially to the rotational axis (4), each end face facing the compressor impeller (2), and a first and second functionally relevant gap dimension (36, 38) is formed in the region of each gap surface. According to the invention, the compressor impeller (2) is designed in multiple parts and has a first impeller shell (10) and a second impeller shell (12). The impeller shells (10, 12) are arranged adjacently to each other axially to the rotational axis (4) in particular, and each impeller shell is at least partly made of a plastic.

What is claimed is: 
     
       1. A side-channel compressor ( 1 ) for a fuel cell system ( 37 ) for conveying and/or compressing a gaseous medium, the side-channel compressor comprising
 a housing ( 3 ), 
 a compressor chamber ( 30 ), which is situated in the housing ( 3 ) and which has at least one encircling side channel ( 19 ,  21 ), 
 a compressor impeller ( 2 ), which is situated in the housing ( 3 ) and which is arranged so as to be rotatable about an axis of rotation ( 4 ), wherein the compressor impeller ( 2 ) has conveyor cells ( 5 ) arranged on a impeller circumference in a region of the compressor chamber ( 30 ), and 
 one gas inlet opening ( 14 ) formed on the housing ( 3 ) and one gas outlet opening ( 16 ), which are fluidically connected to one another via the compressor chamber ( 30 ), 
 wherein the housing ( 3 ) has a respective first and second face ( 32 ,  34 ) each extending radially away from the axis of rotation ( 4 ), each face facing the compressor impeller ( 2 ), and 
 wherein a first and second gap dimension ( 36 ,  38 ) is formed between the first and second face ( 32 ,  34 ) of the housing ( 3 ) and the compressor impeller ( 2 ), 
 wherein the compressor impeller ( 2 ) has a first impeller shell ( 10 ) and a second impeller shell ( 12 ), wherein the impeller shells are arranged adjacent to one another and are each produced at least partially from a plastic, 
 wherein the compressor wheel ( 2 ) is connected to a drive shaft ( 9 ) by means of at least two encircling driver flanges ( 22 ,  24 ), 
 wherein each of the at least two encircling driver flanges ( 22 ,  24 ) is connected by friction connection to the drive shaft ( 9 ) by means of a respective inside diameter, the connection extending radially about the axis of rotation ( 4 ), and 
 wherein each of the at least two encircling driver flanges ( 22 ,  24 ) is in contact with a respective one of the first impeller shell ( 10 ) and the second impeller shell ( 12 ) ( 10 ,  12 ) axially along the axis of rotation ( 4 ). 
 
     
     
       2. The side-channel compressor ( 1 ) as claimed in  claim 1 , wherein, in addition to the impeller shells ( 10 ,  12 ), the compressor impeller ( 2 ) has at least one intermediate element ( 13 ,  25 ,  57 ), wherein the at least one intermediate element ( 13 ,  25 ,  57 ) is situated between the first impeller shell ( 10 ) and the second impeller shell ( 12 ). 
     
     
       3. The side-channel compressor ( 1 ) as claimed in  claim 2 , wherein each of the at least two encircling driver flanges ( 22 ,  24 ) is fixed on the drive shaft ( 9 ) in such a way that each of the at least two encircling driver flanges exerts a preloading force, which runs axially with respect to the axis of rotation ( 4 ), on the respective impeller shell ( 10 ,  12 ) and/or the at least one intermediate element ( 13 ,  25 ,  57 ). 
     
     
       4. The side-channel compressor ( 1 ) as claimed in  claim 1 , wherein at least one of the at least two encircling driver flange ( 22 ,  24 ) has at least one fixing bore ( 20   a, b, c, d ), which extends at least axially with respect to the axis of rotation ( 4 ) and into which at least one fixing pin ( 18   a, b, c, d ), which extends axially with respect to the axis of rotation ( 4 ), of the respective impeller shell ( 10 ,  12 ) projects. 
     
     
       5. The side-channel compressor ( 1 ) as claimed in  claim 2 , wherein the intermediate element ( 13 ) is embodied as a compensating disk ( 13 ), wherein the compensating disk ( 13 ) is produced at least partially from an elastic material. 
     
     
       6. The side-channel compressor ( 1 ) as claimed in  claim 5 , wherein the compensating disk ( 13 ) has at least two openings ( 53 ), which extend at least axially with respect to the axis of rotation ( 4 ), wherein a fluidic connection of the at least one encircling side channel ( 19 ,  21 ) axially along the axis of rotation ( 4 ) is produced in the compressor impeller ( 2 ) by one of the conveyor cells ( 5 ) and by one of the at least two openings ( 53 ). 
     
     
       7. The side-channel compressor ( 1 ) as claimed in  claim 2 , wherein the housing ( 3 ) has a housing upper part ( 7 ) and a housing lower part ( 8 ), wherein the housing upper part ( 7 ) has a cylindrical collar ( 23 ) extending around the axis of rotation ( 4 ), and the housing lower part ( 8 ) has a cylindrical projection ( 26 ) extending around the axis of rotation ( 4 ), wherein the collar ( 23 ) surrounds the projection ( 26 ). 
     
     
       8. The side-channel compressor ( 1 ) as claimed in  claim 7 , wherein a compensating gap ( 43 ) extending radially with respect to the axis of rotation ( 4 ) is situated axially with respect to the axis of rotation ( 4 ) between the projection ( 26 ) of the housing lower part ( 8 ) and the housing upper part ( 7 ), and/or wherein an adjusting disk ( 29 ) extending radially with respect to the axis of rotation ( 4 ) is situated axially with respect to the axis of rotation ( 4 ) between a contact surface ( 33 ) of the collar ( 23 ) of the housing upper part ( 7 ) and a front surface of the housing lower part ( 8 ), wherein at least the first or the second gap dimension ( 36 ,  38 ) between the compressor impeller ( 2 ) and the housing ( 3 ) can be adjusted. 
     
     
       9. The side-channel compressor ( 1 ) as claimed in  claim 2 , wherein a third gap ( 52 ) extending radially around the axis of rotation ( 4 ) is situated axially with respect to the axis of rotation ( 4 ) between the impeller shells ( 10 ,  12 ), wherein the intermediate element ( 25 ) is embodied as at least one O-ring ( 25 ) extending around the axis of rotation ( 4 ), and wherein the at least one O-ring ( 25 ) is arranged in an enlarged gap region ( 28 ) of the third gap ( 52 ). 
     
     
       10. The side-channel compressor ( 1 ) as claimed in  claim 2 , wherein a third gap ( 52 ) extending radially around the axis of rotation ( 4 ) is situated axially with respect to the axis of rotation ( 4 ) between the impeller shells ( 10 ,  12 ), wherein the intermediate element ( 57 ) is embodied as at least one hose-like ring ( 57 ), which extends around the axis of rotation ( 4 ) and has a cavity ( 59 ) in its interior, wherein the at least one hose-like ring ( 57 ) is arranged in an enlarged gap region ( 28 ) of the third gap ( 52 ). 
     
     
       11. The side-channel compressor ( 1 ) as claimed in  claim 1 , wherein at least one recess ( 31 ) is situated axially with respect to the axis of rotation ( 4 ) between the impeller shells ( 10 ,  12 ), wherein a spring element ( 35 ) is arranged in said at least one recess ( 31 ), wherein the spring element ( 35 ) presses the impeller shells ( 10 ,  12 ) axially away from one another and against at least one of the at least two encircling driver flanges ( 22 ,  24 ) by a spring force. 
     
     
       12. The side-channel compressor ( 1 ) as claimed in  claim 8 , wherein at least one of the housing upper part ( 7 ), the housing lower part ( 8 ), at least one of the at least two encircling driver flanges ( 22 ,  24 ), and the drive shaft ( 9 ) is produced at least partially from a metallic material having an identical coefficient of thermal expansion as a metallic material used to produce another of the housing upper part ( 7 ), the housing lower part ( 8 ), at least one of the at least two encircling driver flanges ( 22 ,  24 ), and the drive shaft ( 9 ). 
     
     
       13. The side-channel compressor ( 1 ) as claimed in  claim 12 , wherein the metallic material is aluminum and/or steel and/or a metallic alloy. 
     
     
       14. The side-channel compressor ( 1 ) as claimed in  claim 1 , wherein, at least one of the at least two encircling driver flanges ( 22 ,  24 ) is connected by means of a press fit to the drive shaft ( 9 ) by means of the inside diameter of the at least one of the at least two encircling driver flanges, radially with respect to the axis of rotation ( 4 ). 
     
     
       15. The side-channel compressor ( 1 ) as claimed in  claim 11 , wherein the spring element ( 35 ) is a disc spring ( 35 ). 
     
     
       16. The side-channel compressor ( 1 ) as claimed in  claim 1 , wherein the gaseous medium is hydrogen. 
     
     
       17. A side-channel compressor ( 1 ) for a fuel cell system ( 37 ) for conveying and/or compressing a gaseous medium having a housing ( 3 ), having a compressor chamber ( 30 ), which is situated in the housing ( 3 ) and which has at least one encircling side channel ( 19 ,  21 ), having a compressor wheel ( 2 ), which is situated in the housing ( 3 ) and which is arranged so as to be rotatable about an axis of rotation ( 4 ), wherein the compressor wheel ( 2 ) has conveyor cells ( 5 ) arranged on its circumference within the compressor chamber ( 30 ), and having a gas inlet opening ( 14 ) formed on the housing ( 3 ) and a gas outlet opening ( 16 ), which are fluidically connected to one another via the compressor chamber ( 30 ), and the at least one side channel ( 19 ,  21 ), wherein the housing ( 3 ) has a respective first and second face ( 32 ,  34 ) each extending radially away from to the axis of rotation ( 4 ), each face facing the compressor wheel ( 2 ), and wherein a first and second clearance ( 36 ,  38 ) is formed between the first and second face ( 32 ,  34 ) of the housing ( 3 ) and the compressor wheel ( 2 ) and, wherein the compressor wheel ( 2 ) has a first impeller shell ( 10 ) and a second impeller shell ( 12 ), wherein the impeller shells are arranged abreast to one another axially with respect to the axis of rotation ( 4 ), and are each produced at least partially from a plastic,
 wherein in addition to the impeller shells ( 10 ,  12 ), the compressor wheel ( 2 ) has at least one intermediate element ( 13 ,  25 ,  57 ), wherein the at least one intermediate element ( 13 ,  25 ,  57 ) is situated between the first impeller shell ( 10 ) and the second impeller shell ( 12 ), 
 wherein the at least one intermediate element ( 13 ) is embodied as a compensating disk ( 13 ), wherein the compensating disk ( 13 ) is produced at least partially from an elastic material.